Electric signal for railways.



No. 895,589. PATBNTED AUG. 11, 1908.

J. s. SIMS.

ELECTRIC SIGNAL FOR RAILWAYS.

APPLICATION FILED SEPT,25, 1907.

2 SHBBTS-SHBBT 1.

ww m awr I I I PATENTED AUG. 11, 1908.

J. s. SIMS. ELECTRIC SIGNAL FOR RAILWAYS.

APPLICATION FILED SEPT. 25, 1907.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

JOHN SHERMAN SIMS, OF LONGBEAOH, CALIFORNIA, ASSIGNUR OF ONE-HALF TO EDWARD RICHARD MILLAR, OF LONGBEAOH, CALIFORNIA.

ELECTRIC SIGNAL FOR RAILWAYS.

Specification of Letters Patent.

Patented Aug. 11, 1908.

Application filed September 25, 1907. Serial No. 394,549.

To all whom it may concern:

Be it known that I, JOHN SHERMAN SIMs, a citizen ofthe United States, residing at Longbeach, in the county of Los Angeles and State of California, have invented a new and useful Electric Signal for Railways, of which the following is a specification.

This invention has reference to improvements in electric signal systems for railways, and its object is to' provide means whereby trains will give notice of their approach by visible day and night signals.

The present invention comprises a constantly charged circuit which in its active condition serves to maintain a target or semaphore in an invisible or inoperative condi' tion but when the circuit is broken, either purposely or accidentally, the target will immediately come into view and so notify the engineman of an approaching train that there is danger ahead or that the system is in a dangerous condition by being inoperative.

For night signals a light is rendered visible on the approach of a train into a danger zone so as to give notice a sufficient distance in advance that a train is approaching on the track.

These signals are produced by a system of electric circuits so arranged as to cause the actuation of the signals two or more sections ahead of an a proachingtrain or two or more sections in a vance of an open switch, that is, a switch so placed as to open a siding to trafiic and thus present a dangerous condi tion to an approaching train designed to travel on the main track only. I The invention will be best understood by reference to the following description, taken in connection with the accompanying drawings forming part of this specification, in which,

Figure 1 is a section through a signal box designed to be located at a point visible to an engineman on an approaching train, say upon a pole alongside of the track, said box containing certain mechanisms forming part of the present invention; Figs. 2, 3 and 4 are detail views of portions of the structure shown in Fig. 1; and Fig. 5 is a diagrammatic representation of a system constructed in accordance with the present invention and including a number of signal blocks.

Referring first to Figs. 1 to 4, inclusive,

there is shown in Fig. 1 a box or inclosure 1 of suitable shape to include the various mechanisms comprising the mechanical part of the signal structure. In this box there is a base plate 2 upon which is erected a post 3 carrying an electro-1nag11et 4 which may be of the horseshoe type, and this magnet has in operative relation thereto an armature 5 fast on an arm 6 pivoted at its lower end to the plate 2. there is connected one end of a rod 7, upon the other end of which are formed rack teeth 8 arranged to engage a pinion 9 fast on a shaft 10 mounted in standards 11 rising from the plate 2. Upon each side of the pinion 9 the rod 7 carries guide frames 12 arranged to embrace the shaft 10 so that the rack end of the rod 7 while free to move longitudinally with relation to the pinion 9 is at the same time so held in the frames .12 that the rack and pinion are always maintained in engagement. Upon the shaft 10 there is carried a balance wheel 13.

Upon each side of the pinion 9 the shaft 10 has fixed thereto an arm 14, that is, there are two arms 14, one on each side of the pinion 9. These arms extend away from the shaft 10 in a direction opposite to the rod 7 and each arm 14 near its free end is provided with a longitudinal slot 15. Engaging the slots 15 is a through pin 16 carrying at an intermediate 'point between the arms a pendent plate 17 constituting a target, and this plate is of such size and so related to the other parts that it may be lifted through a slot 18 in the bottom of the casing 1 until it is entirely housed within said casing, or it may be permitted to drop through said slot in the casing until it is exposed to view below the bottom of the casing. In order that this plate may move in a vertical direction the pin 16 is secured to a guide rod 19 passing up through a guide stud 20 in the top of the casing.

The relation of the parts so far described is such that when the magnet 4 is energized and the armature 5 is attracted the arm 6 is at the same time moved toward the magnet and the rack 8 engaging the pinion 9 causes the shaft 10 to be rotated upon its axis in a direction and to an extent suilicient to raise the target 17 until it is entirely housed in the casing 1. When the magnet 4 is denergized To the upper end of this arm the weight of the target and the parts carrying the same is sufficient to cause the target to gravitate to the lower position indicated in dotted lines in Fig. 1.

WVithin the casing 1 is an upright partition 21 supporting a cross partition 22 on which is mounted an electric light 23, which latter, as shown in the drawings, may be of the ordinary incandescent type. Opposite this light are suitable bulls-eyes 24 arranged to be visible in the proper directions, and since the light is intended to indicate a danger condition these bulls-eyes may be made of red glass or may be made of clear glass with a transparent red screen. Arranged within the compartment divided off by the partition 21 is another electro-magnet 25 of the horseshoe type and having an armature 26 connected to a cross bar 27 at the ends of which are contact pins 28 having in their paths contact plates 29 and 30.

Mounted upon the yoke of the magnet 25 between the two coils thereof is a rod 31 extending up through the armature, and upon this rod 31 there is a helical spring 32 the tendency of which is to elevate the armature and move the same away from the magnets. The armature and bar 27 are mounted upon an arm 33 near one end thereof, the other end of this arm 33 being pivoted to a post or standard 34. The circuit connections of the several parts so far described will be described with more particular reference to Fig. 5. In this latter figure are shown several block sections 36 of a railway track, each section being assumed to be electrically continuous for a certain distance, say one half mile more or less, and the meeting ends of the block sections being insulated one from the other, as indicated at 37. One section is shown as including a siding 38 with suitable switches and a switch stand 39.

Extending along the line of railway are two main lines of conductors 40 and 41, the line of conductors 40 being fed by a battery 42 and the line of conductors 41 being fed by a battery 43. It will be understood, of course, that the batteries are only indicative of a source of electric current and may be replaced by a dynamo generator or any other source of current.

The main line conductors 40 are connected one by a branch conductor 44 to one of the terminal plates 30 and the other by a branch conductor 45 to the other terminal plate 30 and including the lamp 23. The other main line conductors 41 are connected one by a branch conductor 46 to the magnet 4 and thence by another conductor 47 to one of the contact plates 29, and the other conductor 41 is connected byabranch conductor 48 directly to the other contact plate 29. The conductor 41 is also connected by a branch conductor 49 to one of the rails of a section 36, two sec- 7 tionsin advance of the location of the" particular signal under consideration, and this same conductor is also connected by another branch conductor 50 to the next section on the other side of the particular section 36 un der consideration. That is to say, if a signal mechanism is located adjacent to one section 36, the conductor 49 is connected to the second section to one side of the section opposite which the signal device is located while the conductor 50 is connected to the section next to the section 36 under consideration but on the opposite end thereof. The other main conductor 41 is connected by a branch conductor 51 to one side of the magnet 25, the other side of which is connected by a con ductor 52 to the opposite rail of the same section 36 to which the corresponding conductor 49 is connected, and this conductor 52 is also connected back by a branch conductor 53 to the same section but to the opposite rail to that to which the conductor 50 leads.

The switch stand 39 is so arranged that when the switch is open to connect the main line to the siding an electric switch carried by said stand but not shown in the drawings will be closed, and its terminals are connected by conductors 54 to the conductors 49 and 52 before referred to but at a point two sections in advance of the railway switch.

Assuming that there are no trains in the neighborhood of a signal box, there is a circuit from the battery 43 through the con ductors 41, magnet 4, branch conductor 47 terminal plates 29 which under the conditions assumed are bridged by the pins 28 and connecting bar 27, the spring 32 maintaining these pins in contact with the plates 29, thence from one of the plates 29 by the branch conductor 48 to the other conductor .41 and back to the battery 43. The magnet 4 being thus energized has drawn its armature 5 toward it and thus turned the shaft 10 in such direction as to elevate the target 17 until it is entirely housed in the casing 1, and, therefore, out of sight. Now, let it be supposed that a train, represented by the wheels 55 and their connecting axle, enters upon a block 36 within two blocks of a signal box. There is now established a circuit from the battery 43 through a branch conductor 49 and another branch conductor 50 to one of the rails of the block upon which the .train has entered, through the wheels and axle to the other rail of the block, thence by a branch conductor 53 and another branch conductor 52 to the magnet 25, thence by a branch conductor 51 to the otherconductor 41 and back to the battery. The magnet 25 being energized attracts its armature 26 against the action of the spring 32 and so breaks the circuit at the contact plates 29 but bridges the contact plates 30. The circuit through the magnet 4 being thus broken the target 17 gravitates to a position below thecasing 1 in which it becomes visible to the engineman of an approaching train, should there be one. At the same time a circuit is established from the battery 42 through a main conductor 40 by branch conductor 45 to the lamp 28, thence to one of the contact plates 30, thence by the pins 28 and bar 27 to the other contact plate 30 and by the branch conductor 44 and main conductor 40 back to the battery 42. This at once lights up the lamp 23 and displays a red signal which will indicate at night a danger condition to the engineman of an approaching train, should there be one.

As soon as the train leaves the block under consideration and enters the next block the same operations transpire in the next succeeding signal box while in the box first considered the breaking of the circuit through the magnet 25 releases the armature 26 and the spring 32 returns the bar 27 and its pins 28 to the initial position in contact with the plates 29 and out of contact with the plates 30. As a result of this operation the light 23 goes out and the magnet 4 is again energized,thus lifting the target 17 out of sight. Suppose, however, that the train approaches in the other direction from that considered. Again the magnet 25 will be energized through the branch conductors 49 and 52 and the same operation will be performed in the display of signals. It will thus be seen that the signals are displayed two blocks ahead whether the trains are going in one direction or the other. Of course it will be understood that the switch stand 39 is con nected up. by the conductors 54 in both directions so as to display signals on both sides of the railway switch at a sufficient distance to warn approaching trains.

Now, let it be supposed that a train is progressing along the track and has caused a signal to be displayed. As soon as the train enters the next block the signal is cut out and the next succeeding signal is rendered active. When the third block is reached the signal two blocks ahead is displayed but at at the same time a signal two blocks behind is likewise displayed, since the conductors 49 and 52 are branched off to the advance block, and, therefore, the signal which was first operated by the approaching train and then again rendered inoperative by the passing of the train is again rendered operative when the train has reached a position two blocks ahead of the signal, and so a moving train not only displays danger signals two blocks ahead but likewise displays danger signals two blocks in the rear. By this means a moving train is preceded and succeeded by danger signals and thus is protected from both head-on and rear-end collisions, the train being located approx]- mately in' an intermediate position in the zone of displayed signals.

I claim 1; In an electric signal system for railways, a charged electric circuit extending along the line of way, electro-magnets nor mally included in said circuit and charged thereby, signal targets held in inoperative position by the normally charged magnets, other normally uncharged electro-magnets in multiple-arc relation to the first-named magnets, connections from the second-named magnets to circuit-closing means under the control of trains traveling upon the railway, and means under the control of the second-named mag nets when the latter are charged for breaking the circuit to the first-named magnets and thereby causing the movement of the signal targets to operative position.

2. In an electric signal system for railways, a charged electric circuit extending along the line of way, electro-magnets normally included in said circuit and charged thereby, signal targets held in inoperative position by the magnets when charged, other electro-magnets in multiple-are relation to the first-named magnets, connections from the second-named magnets to circuit closing means under the control of trains traveling upon the railway, means under the control of the second-named magnets for breaking the circuitto the first-named magnets, another charged circuit extending along the line of way, branch circuits therefrom including electric lights, and circuit terminals under the control of the second-named electro-magnets for completing the circuit through the lights.

3. An electrically operated signal for railways, comprising an electro-magnet, an armature therefor, a rotatable shaft, connections between the magnet armature and the shaft for rotating the latter when the magnet is energized, slotted arms carried by the shaft, and-a guided target having a pin engaging the slots in the arms of said shaft.

4. An electrically operated signal for railways, comprising an eleetro-magnet, an armature therefor, a rotatable shaft, a pinion upon said shaft, a rack engaging said pinion, connections between the rack and the electro-magnet, guide plates embracing the shaft and carrying the rack, slotted arms carried by the shaft, and. a guided target pendently supported from said arms and movable longi tudinally with relation to the slots therein.

5. An electrically operated signal for railways, comprising an elcctro-magnet, a target normally concealed when the magnet is energized and displayed when the magnet is de energized, said target being controlled by said magnet, a charged circuitincluding an electric lamp, opposed sets of circuit terminals, one set including the magnet and theother set including the lamp, another electro- I In testimony that I claim the foregoing as magnet, a spring-controlled armature there my own, I have hereto affixed my signature 10 for, and a bridging conductor in operative in the presence of two Witnesses. relation to both sets of circuit terminals and JOHN SHERMAN SIMS.

- 5 normally held in engagement With that set of terminals controlling the first-named magnet l/Vitnesses:

by the action of the spring controlling the E. R. MILLAR, armature. C. E. HUNTINGTON. 

